A wireless communication system is a complex network of systems and elements. Typically elements include (1) a radio link to the mobile stations (e.g., cellular telephones), which is usually provided by at least one and typically several base stations, (2) communication links between the base stations, (3) a controller, typically one or more base station controllers or centralized base station controllers (BSC/CBSC), to control communication between and to manage the operation and interaction of the base stations, (4) a call controller (e.g., a mobile switching center (MSC)) or switch, typically a call agent (i.e., a “softswitch”), for routing calls within the system, and (5) a link to the land line or public switch telephone network (PSTN), which is usually also provided by the call agent.
For many people, the Internet has provided alternative ways of communication. In particular, electronic mail messages (i.e., e-mail) have replaced traditional letters and sometimes voice calls as a way of communicating. However, e-mail may not provide a response fast enough in certain circumstances. Further, multiple exchanges of e-mails may require a number of steps to read, reply, and send the e-mails back and forth. Accordingly, real-time communication service such as instant messaging (IM) service and group chat service is becoming a communication mechanism to substitute for e-mail. For example, instant messaging service permits a subscriber to determine whether other subscribers such as friends or co-workers are connected to the Internet, and if so, to communicate with each other in “real time” over the Internet. Under most circumstances, real-time communication is “instant.” Even during peak periods of the Internet, delay of real-time communication is typically less than a few seconds. Thus, subscribers may have a real-time online “conversation” by exchanging messages with each other (i.e., sending messages back and forth). For example, parents may be able to “talk” with their children who are attending college or working in other cities, states, or countries via real-time communication service. As a result, real-time communication service may even replace voice calls because of cost and convenience.
One aspect of designing a wireless communication system is to provide real-time communication service to mobile stations, i.e., wireless devices such as cellular telephones, pagers, and electronic planners. In particular, a real-time communication message may include a voice message, a textual message, an image file, a video file, and an audio file. In addition, the real-time communication message may include more than one component (e.g., a voice message and an image file). Thus, a subscriber may prefer to receive one component of the real-time communication message on one wireless device and receive a second component of the real-time communication message on a second wireless device. Further, the subscriber to real-time communication service may prefer to receive a real-time communication message in a particular format. While attending a meeting or a seminar, for example, the subscriber may prefer to receive the real-time communication message in textual message format via a cellular telephone even though the cellular telephone may be operable to receive a message in either voice message format or textual message format. However, wireless devices have resource limitations such that the wireless devices may not be operable to handle certain contents and files of a real-time communication message. For example, a pager and an electronic planner may not be operable to handle a voice message whereas a cellular telephone may be more adapted to send and receive a voice message but not an image file or a video file.
Therefore, a need exists for a method and a communication network to route a real-time communication message based on the resource of a wireless device and the preference of a subscriber.